Grist for the Mill

[Farrell]

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5 cents per year? Quite unreasonable. With only one exception, pianos =
that I tune regularly - at least once per year (and most only once per =
year) - never need a pitch raise - and if any were 5 cents flat, it =
would need a pitch raise. Two cents or less per year would be my =
estimate. Do you find pianos that have not been tuned for 10 years to be =
50 cents flat? I find that it takes more like 25 or 30 years (or more) =
to go 50 cents flat.

Terry Farrell

  Oh, yeah? Well they laughed at Rodney Dangerfield, too!=20

  Okay, maybe it's a not-so-stable piano, who knows? As we go about =
tuning, let's all the folks with ETDs experiment a time or two ...=20

  How far do you you turn a pin to bring a piano up 50 cents? Let's say =
the sucker is only tuned every ten years, falling 5 cents a year (not =
unreasonable, Shirley). That makes 10 tunings at 50 cents flat each =
time. I'm thinking that's good for about 4 additional coils, minimum ...

  Let the Cyberspace Electrons fly! It ain't over yet ... the fat lady =
is still in the wings, eating wings, awaiting a curtain call.*

  Alan Barnard
  Helmut Still On, One Minor Dent, in Salem, MO

  *You can identify the call of the Western Red-Tufted Curtain by its =
swooping hoop, rising half a semitone while the bird lifts its head up =
about 135 degrees (Fahrenheit).

    ----- Original Message -----=20
    From: Farrell=20
    To: Pianotech
    Sent: 05/11/2005 8:18:33 PM=20
    Subject: Re: Grist for the Mill


    A 30 degree turn of a tuning pin every year on a stable piano? No =
way!

    Calculate the pitch increase with a 30 degree rotation on a 2/0 pin =
- even the 7.5 degree rotation - I suspect you will very quickly realize =
your numbers are grossly excessive.

    Unless, of course, I am wrong. But I don't think so.

    Terry Farrell
      ----- Original Message -----=20
      From: alan and carolyn barnard=20
      To: Pianotech=20
      Sent: Wednesday, May 11, 2005 8:50 PM
      Subject: Grist for the Mill



      We recently had a long dialog on here about the actual changes in =
a piano that has gone flat. There was much poo-pooing (can we say that =
on TV?) from some folks of the notion that tuning pins turned =
counter-clockwise when pianos go flat. Their arguments were logical and =
some folks even produced mathematics to demonstrated that pin reversal =
is unlikely.

      BUT ...

      I was thinking about this on my way home from PTG chapter meeting =
(2.5 hr drive) and came up with a little point of logic which suggests =
that the pins MUST move. See what you think ...

      Virtually all pianos go flat over longish time periods and =
certainly are found flat more often than sharp if you go through a whole =
cycle of season changes, i.e., an annual tuning. When we bring a flat =
string up to pitch, it tends to increase the width of the coil slightly =
every time we turn the pin. If the pin is turned one full =
revolution--360 degrees--over years of tuning, this would add the =
thickness dimension of the wire to the overall coil width and one full =
wire wrap to the number of coils.=20

      You with me?

      So let's take a hypothetical piano string--say a very stable 1905 =
Howard upright A4 middle string--that has averaged (let's be =
conservative...) falling flat enough that a 7.5 degree turn of the pin =
was required each year to bring it up to pitch. Now 7.5 degrees is a =
fairly small annual adjustment, just a little tweak, actually. Ce n'est =
pas? It's only 1/6 if a quarter turn.

      So, between 1905 and 2005, we have turned that string's pin 100 X =
7.5 =3D 750 degrees, more than two full turns.

      How many old pianos do we run into that have five or more coils on =
the pin? I never noticed any.  In fact, most seem to have the original 3 =
coils standing about as far from the plate as the day it was =
strung--unless someone has hammered them in, in which case it's still =
only about 3 coils!

      Pause ... thinkin on that?

      Now strings must become ever so slightly thinner as they stretch, =
especially in the earlier years. So, for the string to produce the same =
pitch, the string tension required would be ever so slightly less over =
time. This would have a very slight mitigating effect on the thought =
puzzle proposed above. But nowhere near enough to explain 100 years of =
flatness, methinks. And ven if the string is stretching, you would still =
be adding linear length to the coil every time. =20

      I believe, in fact, that about a 30 annual correction, or more, =
would be very common.  Think about your own real-world, real-piano =
experience. Visualize pulling your tuning hammer through a 30 degree =
arc, i.e., 1/3 of a quarter turn. That's still a pretty darned small =
once-a-year adjustment. So, I think my estimates here have been very, =
very conservative.

      Anyway, at 30 degrees the piano would have to have a total of 8+ =
full coils on every pin if the pin never turned backward.

      Your turn or, as we used to say in Viet Nam .... I n c o m i n g ! =
! !=20

      Alan Barnard
      Hunkered in the Bunker in Salem, MO


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